Who Is Mimi O'Donnell? 9 Things You Need to Know About Philip Seymour Hoffman’s Lady

In the wake of Philip Seymour Hoffman's tragic death, friends and fans have expressed concern for the three children he left behind. Fortunately, they are not alone — they still have their mother, Mimi O'Donnell. But who is the woman who occupied the center of Hoffman's life?

Surprisingly little is public about Hoffman's partner of nearly 15 years and the mother of his children. But here is what is known about the woman who maintained such a low profile while staying at his side for so long.

1. She's a Philly girl. O'Donnell attended the Philadelphia College of Textiles and Sciences — now called Philadelphia University — and graduated with a major in fashion and a minor in textile design.

2. Almost a denist. Costumes and fashion wasn't always her dream; Mimi took her time finding her path. "I spent my freshman year at school in Lancaster, Penn., doing secondary ed," she told Living Design Online in 2001. "It was something I enjoyed for a time, but then I spent time student-teaching, and I realized I didn't want to do that. So I took a year off and worked in a dentist's office as a hygiene assistant. But that wasn't really what I wanted to do either, so I started taking classes at Philadelphia Textile." And, after a few interviews with fashion houses, she started working as an assistant designer or stitcher in local Philadelphia theaters.

3. She's a 20-year New Yorker as of this year. After spending 1993 at the Williamstown Theatre Festival in Massachusetts, Mimi was offered a job at Playwrights Horizons in NYC in 1994. "After that, I continued to take every job I could," she said.

4. In 1999, she met her match. Twice. O'Donnell took a gig with the Labyrinth Theater Company to do the costumes for the play "In Arabia We'd All Be Kings," which Hoffman directed. They fell in love and she remained with the Company, eventually even becoming its Artistic Director (more on that below). We call that a win-win.

5. She is the mother of Hoffman's three children: Cooper Alexander, born 2003; Tallulah, born 2006; and Willa, born 2008. The couple was often seen walking in their New York City neighborhood with their little ones in tow and Philip seemed to make time with his children a priority.

6. She worked in TV. O'Donnell served as an assistant costume designer on "Saturday Night Live" from 2001-2002, and, more recently, "A Gifted Man," a failed 2011 series from CBS starring Patrick Wilson.

7. In addition to remaining a wife-like partner and the mother of his children, O'Donnell served as the costume designer on Hoffman's directorial debut, "Jack Goes Boating." Mimi also received a "special thanks" shoutout in the credits for "Capote," the film that earned Hoffman his Oscar.

8. In April 2013, Mimi was named the artistic director of the Labyrinth Theater Company (a position formerly held by Hoffman). At that time, she revealed that she was shifting her focus away from costume design so that she could instead produce three plays per year at the Bank Street Theater in the West Village, as well as to continue its free Barn Series readings of plays in development. "I want us to make sure that great artistic experiences keep happening on a consistent basis," she explained of her decision at the time. Hoffman remained on the Board of Directors for the Company at the time of his death.

9. Hoffman and O'Donnell reportedly were not living together at the time of his death. The star allegedly moved into the apartment on Bethune Street, which was supposedly rented as office space initially, in fall 2013. O'Donnell remained living in their joint apartment on Jane Street, just a few blocks away. Yahoo confirmed with the NYPD that they have been in touch with her, but could not confirm any further details regarding their living situation.